Communication networks are well-known in the computer communications field. By definition, a network is a group of computers and associated devices that are connected by a communications facilities or links. Network connections can be of a permanent nature, such as via cables, or can be of a temporary nature, such as connections made through telephone or other communication links. Networks vary in size, from a local area network (LAN) consisting of a few computers and related devices, to a wide area network (WAN) which interconnects computers and LANs that are geographically dispersed. An internetwork, in turn, is the joining of multiple computer networks, both similar and dissimilar, by means of gateways or routers that facilitate data transfer and conversion from various networks. A well-known abbreviation for internetwork is "internet." As currently understood, the capitalized term "Internet" refers to the collection of networks and routers that use a Transmission Control Protocol/Internet Protocol (TCP/IP) to communicate with one another.
Use of LANs, WANs and the Internet has recently seen explosive growth due to the increased ease in the ability to link geographically dispersed computers. As the amount of information distributed across these networks grows, and the speed with which information can be added or changed at any one location on a network increases; the risk of information becoming stale and outdated elsewhere in the network increases significantly and the tolerance for stale or outdated information decreases dramatically. Thus, specialized information management is needed which automatically updates distributed information and instills confidence in the validity or freshness of the updated information.
Heightened public and private awareness of environmental and ecological concerns has also created a need for specialized information management over WANs, LANs and the Internet. Problems of a tangible nature, such as landfill shortages, and problems of a less comprehensible nature, such as ozone depletion, have brought waste reduction and recycling to the front page of many fields of design, engineering, planning, and legislation.
Professional practices in the fields of design, engineering, planning, and legislation require the specification of materials to be used during production and/or construction of an object or environment. Informed materials selection, if done properly, can greatly reduce the stress put on ecosystems and societies by specifying "sustainable" materials and processes. Additionally, through the use of resources that enable responsible material selection at the outset of a project, the potential need for costly design changes later in the project lifecycle may be minimized.
The goal of providing environmentally responsible and sustainable materials and processes is a difficult one due to the diffused nature of the varied sources of information. Object and image creators require a designed, comprehensive research tool or reference resource to allow them to make inherently responsible and necessary choices quickly. Currently, time is the primary inhibitor of such research. Usually, by the time the appropriate information is located, the project is already done and "out the door." To provide the information necessary to the making of informed materials decisions, a resource is needed that will unify and organize the necessary information in one place.
In addition to the need for information management to facilitate research in the areas of ecologically responsible materials, materials processing, and materials recycling, there is also a need to make on-line communications and programs act in a more intuitive, less confusing, and less costly manner.
In summary, the Internet and various other LANs and WANs serve as a vast conduit of information to anyone using them. The proliferation of information on these networks has created the need for a method and apparatus to automatically update information distributed across a network. The method and apparatus should be capable of instantly communicating updated or new information to any network member or node that has shown an interest in that type of information, without a specific request for the updated or new information. Further, the method and apparatus should provide automatic propagation of information to all interested users while maintaining acceptable fault tolerance and efficient bandwidth use. As described in the following, the present invention provides a method and apparatus that meet these criteria and solves other shortcomings in the prior art.